1. Field of the Invention
The invention relates to a machine for the lengthwise treatment of webs of corrugated board, which is regularly a lengthwise cutting and/or grooving machine.
2. Background Art
In machines of the generic type known from U.S. Pat. No. 4,976,676 and U.S. Pat. No. 6,071,222, tool beds are housed by twos in a machine frame and can be moved toward, and away from, each other by means of suitable drives. Tool holders are disposed on the tool beds, which are allocated to each other by twos and which are displaceable crosswise of the conveying direction of a web of corrugated board that is passed between them. Each pair of tool holders holds a pair of tools consisting of a tool and a counterpart tool, which may be grooving tools or cutters. The tool holders are displaceable between lateral parking spaces and a working area located therebetween, the working area corresponding to the greatest possible width of the web of corrugated board to be treated. In the at least one lateral parking space, the tool holders, which include the tools and counterpart tools, are parked when not in use. This known design of lengthwise treatment machines can be used also within the scope of the invention. For displacement of the tool holders from the at least one parking space into the working area, threaded spindles are provided, with a spindle being allotted to each tool holder. A spindle nut is non-rotatably disposed in each tool holder so that, upon rotary actuation of the threaded spindle that is allotted to the respective tool holder, the tool holder is displaced on the corresponding tool bed crosswise of the conveying direction of the web of corrugated board either into its operating position in the working area or out of it into the associated parking space or, within the working area, from one operating position into another. Each threaded spindle has an actuation of its own. This design is very reliable and works very rapidly; however, it is complicated in construction and thus rather costly.
It is an object of the invention to embody a machine for the lengthwise treatment of webs of corrugated board of the type mentioned at the outset such that the constructional requirements of crosswise tool holder displacement are reduced.
According to the invention, this object is attained in a machine for lengthwise treatment of webs of corrugated board, comprising a machine frame; a first tool bed, which is movable from a position of rest into a working position and back again; at least one threaded spindle, which is disposed in the first tool bed and which is rotatably drivable; several tool holders, which are disposed on the first tool bed on a first side of a web of corrugated board and supported for displacement crosswise of the conveying direction of the web of corrugated board, and which have a tool, and the number of which exceeds the number of the threaded spindles, and which have a spindle nut, which is disposed on the threaded spindle, and which is rotatably mounted in the tool holder; a supporting arrangement for the web of corrugated board disposed on a second side of the web of corrugated board; and a clutch, by means of which to couple the spindle nut non-rotatably with the tool holder. This gist of the invention resides in that several tool holders are drivable by a single threaded spindle and that the respective tool holders may be selectively coupled with the threaded spindle.
There are several possibilities of supporting the web of corrugated board on a side opposite the tools. For instance, a rotatable, circular cylindrical brush that extends substantially over the full width of the web of corrugated board may be used as a support arrangement, which is known from EP 0 443 396 B1. Use may also be made of counterpart tools that are allocated to the tools and are disposed for crosswise displacement on a tool bed in the same way as the tools.
Further features, advantages and details of the invention will become apparent from the ensuing description of two exemplary embodiments, taken in conjunction with the drawing.